Whitney, in an exclusive interview with The Post, called Citigroup Chief Executive Vikram Pandit and his minions “naive” for their continued belief that the bank can shrug off recent massive share-price declines.

“Pandit and his executives are completely naive if they think the share price is not important,” Whitney fumed. What is more, the Oppenheimer bank analyst balked at Pandit’s belief that Citigroup can continue down the same path it has traveled for the past year, foregoing the sale of major assets like Smith Barney or the credit-card business.

“Pandit is wrong, Citi will not be able to stay in its current form,” she said, adding that the banking giant must break itself up and sell off the pieces to raise capital and reduce its size.

“Citigroup is in such a mess Stephen Hawking couldn’t turn this company around,” the money maven added. “It has lost the most money of all the banks, and has the greatest leverage.”

Whitney spoke to The Post at the end of Citi’s most disastrous week in the last 10 years.

The share price closed down 20 percent on Friday, to $3.71, after losing more than 60 percent of its value in the preceding week.

Once the biggest bank in the world, the embattled Citigroup is worth just $20 billion today, compared to $250 billion in 2006. Not even the prospect of a $350 million cash injection from Saudi Prince Al Waleed bin Talal was enough to reverse the tumbling share price.

The only bright spot in the entire week was a brief respite before the market opened on Friday as a rumor leaked out that the Citi board was to meet to discuss a breakup of the group or a merger with another bank.

But Pandit soon ended the fun as another leak cited the Citi chief’s opposition to a breakup of the group, and in particular, his unwillingness to sell Smith Barney.

Senior sources within Citigroup were fighting the share-price fire all week, trying to boost the bank’s standing with investors and the media as speculation mounted that Citi could follow Lehman Brothers and Bear Stearns into the banking graveyard.

The senior sources claimed that Citi is very different from banks that have collapsed in the credit crunch because it is well capitalized.

Still, Pandit is expected to be huddling today with executives and conferring with government officials and an announcement regarding more federal assistance or a spin-off of assets could come later on Sunday.

But Whitney took issue with the bank’s defense.

“Citi is wrong if they say they are adequately capitalized. No bank is adequately capitalized today and Citi is no exception,” she said.

Whitney gained notoriety in 2007 when she published a damning research note about Citigroup, claiming the bank needed to cut its dividend and sell assets to avert a $30 billion capital shortfall.

Citi lost more than $15 billion of market value in the carnage that ensued and Whitney started getting death threats from the bank’s investors.

Her note sparked a broader sell-off that wiped $369 billion off the value of the Dow Jones industrial average, which led to her pro-wrestling husband – 6-foot-6, 300-pound John “Bradshaw” Layfield – canceling his travel plans to protect her.

Whitney expects the Citi share price to keep falling until Pandit takes decisive action – but warned it has not got much farther to go.

“The company cannot raise capital, there are no buyers even if he [Pandit] wanted to sell Smith Barney,” Whitney concluded.